The term is generally used to refer to a localized instability due to a chromosomal site that contains a small number of nucleotides repeated in tandem. As a result of slippage during replication the number of repeated sites may be increased or decreased. If this repeated segment is in a structural gene, it may be converted to a poorly or nonfunctioning allele. The term microsatellite instability is used synonymously. See Huntington disease (HD). Contrast with genetic instability.
Subjects: Medicine and Health — Genetics and Genomics.